With a magnitude of 7.8, it made the list of the world’s strongest quakes, with the same intensity as the one in Nepal on April 25. Fortunately, the Japan quake was centered more than 500 miles offshore, and no tsunami warning was issued for the coast near Tokyo.
The cause for both the Nepal and Japan quakes wasn’t fracking, or any other human activity. It was the Pacific Rim.
Coastlines all around the Pacific Ocean have been subject to earthquakes and volcanic eruptions for millions of years, making that ocean much less peaceful than its name suggests.
The Pacific occupies its own tectonic plate. To the west, it is bordered by the next pieces in the global mosaic, the Eurasian and Australian plates. At the eastern Pacific coast, the American plate carries North, Central and South America. A few smaller pieces complete the puzzle.
Tectonic plates are in constant motion. Where two of them grind alongside each other, as they do in California, earthquakes occur almost daily at different magnitudes.
Sometimes they get stuck for a while, locked in a struggle to break loose while tension is building up. When that finally happens, the ground gets displaced in a jolt that can measure several dozens of feet.
Imagine your home or office building, suddenly thrown sideways by 10 yards, and you get an idea of what happened in the Great San Francisco Quake of 1906.
The island nation of Japan is in a particularly troubled part of the Pacific Rim. Hokkaido, Honshu, Shikoku, Kyushu and several hundred smaller Japanese islands are located on a fault line that extends southward through the Philippines and Indonesia. All these regions, unfortunately, are among the most densely populated in the world.
127 million people in Japan, plus 100 million in the Philippines, plus another 256 million in Indonesia makes for roughly half a billion inhabitants living in a huge danger zone.
As a technological leader among world nations, Japan is better equipped to deal with disasters than its poorer neighbors to the south.
Considering the likelihood of quakes, tsunamis, volcanoes, plus the typhoons (hurricanes) that build in the western Pacific every summer, this part of the Pacific Rim will remain troubled for many more centuries.
Rudi Kiefer, Ph.D., is a professor of physical science and director of sustainability at Brenau University.